Python内省与反射巧妙运用示例

x = 5
print(type(x))  # 输出 <class 'int'>

import math
print(dir(math))  # 输出 math 模块的属性和方法列表

class Person:
    name = "Alice"

person = Person()
print(hasattr(person, "name"))  # 检查对象是否有名为 "name" 的属性
print(getattr(person, "name"))  # 获取对象的 "name" 属性的值
setattr(person, "name", "Bob")  # 设置对象的 "name" 属性的值

import inspect
def example_function():
    pass
print(inspect.getsource(example_function))  # 获取函数的源代码

class MyClass:
    pass

MyDynamicClass = type("MyDynamicClass", (), {})  # 动态创建类
my_instance = MyDynamicClass()  # 创建类的实例

class MyCalculator:
    def add(self, x, y):
        return x + y

calculator = MyCalculator()
method_name = "add"
result = getattr(calculator, method_name)(2, 3)  # 动态调用方法

class Person:
    name = "Alice"
person = Person()
attribute_name = "name"
value = getattr(person, attribute_name)  # 获取属性值
setattr(person, attribute_name, "Bob")  # 设置属性值

class Person:
    name = "Alice"
def dynamic_method():
    print("Dynamic method")
# 内省：获取对象的类型和属性
x = 5
print(type(x))  # 输出 <class 'int'>
print(dir(x))
# 反射：动态创建类、方法和调用方法
MyDynamicClass = type("MyDynamicClass", (), {})
my_instance = MyDynamicClass()
setattr(my_instance, "dynamic_method", dynamic_method)
my_instance.dynamic_method()  # 输出 "Dynamic method"
# 应用场景：插件系统
class Plugin:
    def perform_action(self):
        print("Plugin action")
plugin_name = "Plugin"
plugin_class = globals()[plugin_name]
plugin_instance = plugin_class()
plugin_instance.perform_action()  # 输出 "Plugin action"